Metal bar straightening machine



Nov. 15, 1949 F. J. KENT METAL BAR STRAIGHTENING MACHINE Original Filed July 16, 1945 2 Sheets-Sheet l mms/mx. fm/vc/J J Kia/7 T TOQNEYS F. J. KENT METAL BAR STRAIGHTENING MACHINE Nov. l5, 1949 original Filed July 1ra, 15345 2 Sheets-Sheet 2 A TTO'Q/VfYS musulman me J. nent, Farm mu. N. Y.. um u Hydropress, Incorporated, New York. N. YmawyF-f corporation of Delaware i Original application July 16. 1945, Serial No.

605,271. Dividedand `this application Septembei' 3, 1949, Serial No. 114,024

6 Claims. (Cl. 153-35) l This invention relates to a machine for straightening metal bars and particularly profiled or iianged bars of nonferrous metalssuch as aluminum, magnesium, their alloys andthe like.

'Bars of intricate shape and large size are pro;

duced by extrusion methods and they become deformed for various reasons after extrusion so that they are buckled or twisted either locally or throughout their entire length. It, therefore, is necessary to remove buckling and twists in' the barsl by some. convenient method.

One of the objects of the present invention is to provide a machine having gripping heads with passages completely through the heads and grippers in said heads so that the bars can be passed completely through the machine and gripped between any desired points along the bar. The bar can be gripped and one of the heads moved relative to the other head, which has been previously anchored, so as to stretch the same beyond its yield point and thus remove any buckle that may be therein. If the bar has a twist therein, the present machine provides means for twisting the same in the opposite direction beyond the yield point of the metal so as to untwist the bar. Considerable force is necessary in order to perform these operations. It is preferred that the force applying means be attached to the longitudinally movable head in such a manner that said means is not rotatable as the head is rotated in an untwisting operation. This has proven to be quite diilcult because of the high forces involved. In the preferred form of the straightening machine, hydraulic force is employed for the longitudinal stretching action and when such is used it has been found preferable not to rotate the hydraulic piston as the longitudinal force is applied to the stretching and detwisting head. One preferred form of thrust bearingcomprises a divided radial roller bearing.

In one form of the invention, the hydraulic piston for stretching purposes is hollow for the passage of the bars therethrough, as described and claimed in applicants co-pending application, Serial No. 605,271, filed July 16, 1945, of which this application is a division. In the form of the invention described and claimed herein, the hydraulic .piston or pistons are parallel with a central tube and -crosshead, with connecting bars for transmitting the force of the hydraulic means to the stretching and detwisting'head.

Bars or shapes can be placed in the machine by passing them through the hollow gripping heads and then adjusting the position thereof so 2 as to lock the desired portions of the barbetween the two gripping heads. The bar then can be subjected to a stretching and/or detwisting operation. These and other objects of the in vention willv become apparent from the following description and drawings which are merely exemplary.

In the drawings: Figure 1 is a broken longitudinal elevation par- Atially'in section of the invention.

Figure 2 is a fragmentary plan view partly i section of the headstock andhydraulic cylinder vof the form shown in Figure l. l

Figure 3 is an enlarged fragmentary sectional view of the headstock of Figure 1 showing details of the thrust bearing construction.

Referring to Figure 1, tailstock 49 is adjustably mounted on bed 50 and is ilxed in position there on by means of anchor 5l engaging stop 52 in the bed 50, said tailstock having work gripping iingers 53. Headstock 54 has gripping ilngers 55 operable by hydraulic pistons 56. Non-rotatable headstock housing 51 (Figs. 1 and 2) has connectors 58 (Fig. ,2) extending to crosshead 59. Crosshead 59 has two hydraulic pistons 69 mounted in hydraulic cylinders 6|, said pistons being connected to said crosshead at 62. Telescoping tube arrangement 63 may be provided centrally ofthe gripping head to serve as a guide for the bars being passed through the headstock. `The housing 51 can be slidably mounted on the bed by means of suitable feet to assist in preventing rotation of the housing.

When it is desired to perform a stretching operation, hydraulic pressure admitted into hydraulic cylinders 6I will cause connecting bars 58 to'move to the left with crosshead 59, said bars being connected thereto by pins 64. In order to return the headstock, hydraulic cylinders 65 are provided, the pistons thereof Being connected by rods 65 toI crosshead 59 at an extension of pins 64. The various hydraulic cylinders 6| and 65 are mounted on the frame s'o as to be nonrotatable with respect thereto, and may assist in,

holding housing 51 from rotation although normally all tendency of housing 51 to rotate will be prevented by the machine frame.

The headstock housing is provided with a worm wheel arrangement for turning gripping head 61. The worm wheel is seen at 68, said wheel being rotatably by a worm driven by motor 68. A roller thrust bearing assembly has a plurality of longitudinally sub-divided rollers 69' and 10 of rotation ofthegripplng head. Rollers 69 and 10 are separate and may rotate at different speeds relative to each other. When non-rotatable headstock housing 51 is moved to the left, the thrust will be transmitted through ring 13 and the frame relative to the second head. said second housing being non-rotatable. means conradial split thrust -rollers to the rgvlat`atable gripping head-61.

When it is desired to straighten a bar or shape, y such shape is moved through the open passageways through the headstock,v and tailstock, it

beingpossible to feed the shape, for-example,`

from right't'o left through a tailstock, although the feeding may be in the opposite direction. The

tailstock and headstockv are adjusted relative to each other'so that the bar may be gripped at the desired points and the control mechanism then operated so that the gripping lingers 53 and 55 firmly grip the bar. Pressure may-be applied to hydraulic cylinders 6I to stretch the, bar as it is pulled therein. Y

If the bar has a twist, motor 68' oanbeve'nernected with the second head for lrotating the same, a hydraulic `motor located on either side oi the passageway for the bars through the second head, a crosshead connecting the pistons of said motor, longitudinally extending means for connecting said crosshead to said non-rotatable housing of the second gripping head, thrust bear- Ving means located between said housing of said second gripping head and the rotatable gripping head thereof so'that longitudinally exerted torce can be transmitted to the rotatable head,'a telescoping bar guidelocated between said crossgized and the headstock'body or gripping head B1 rotatedl thereby, thecasing or headstock housing 51 not rotating therewith. The thrust bearing permits .such rotation under the possible highl pressure involved. If itvis'desired to stretchand tions may be made to theembodiments and details of construction, including variations of thef-orm of the thrust bearing without departing from the spirit of the invention except as deined in the appendedclaims.

What is claimed is:

1. In a machine for straightening bars of the character described, a frame, two gripping heads mounted on said frame, said heads having housings and having aligned passageways therethrough for the passage 'of bars from end to endA of and through the machine, bar gripping means head and the rotatable lgrippinghead, and means connecting said second gripping headhousing and pistons with said frame for preventing relative rotation of the rhousing and-frame.

3. In a machine for straightening bars lcharacter described, va frame, two gripping heads.A

mounted onsaidv frame, ,said heads "having husings and having aligned v'passageways therethrough for the lpassage of bars from end to end of and through the machine, bar gripping .means in each of said 'heads for holding bars at spaced points, 'anchoring means :on the first of said gripping heads adjustablypositioning said'head second gripping head and the rotatablegripping 1 head thereof so that longitudinally exerted force on the frame relative to the second'head,l said second housing being non-rotatablmmeans con 'nectedwith the secondhead for rotating the same,'a hydraulicmotorlocatedon either side of the passageway for the barsv through the second head,'a orosshead connecting the pistons of said motor, longitudinally extendingmeansiorconnecting said crosshead to said non-'rotatable housing of the second gripping head, thrust bearing means located between said housing of said can be transmitted to the rotatable head, hydraulic motor vreturn means mounted on said machine and connected with said second housing for moving -said 'housing in a direction opposite to Athat of the rst mentioned hydraulic motor, and means connecting said secondl gripping head' housing and pistons with said frame in each of said heads for holding bars at spaced f points, anchoring means on the first of said gripping heads adjustably positioning said head :on

the frame relative to the second head, said second housing being non-rotatable, means` connected with the second head for rotating the same, a hydraulic motor located on either side of the passageway for the `bars through the second head, a crosshead connecting the pistons of said motor, longitudinally extending means for connecting said crosshead tosaid non-rotatable.

housing of the second gripping head, thrust bearing means located between said housing of said second gripping head and the rotatable gripping head thereof so that longitudinally exertediorce can be transmitted to the rotatablev head, and

'for preventing relative rotation ofthe housing and frame.

4. Ina machine for straightening bars of the character described, a frame', twojgripping heads mounted on said frame, said. heads having housings and 'having aligned passagewaysA therethrough Afor the passage of bars-from end to end of and through the machine, bar gripping means in each of said heads for holding bars at spaced points, anchoring means on the rst of said gripping heads adjustably positioning said head on the frame relative tothe second head, said second housing being non-rotatable, means connected with the second head for rotating the same, hydraulic cylinders andpistons mounted on said frame on either side of the passageway for the bars through the second head, a crosshead connecting s'aid pistons, longitudinally extending means for connecting'rsaid crosshead to said non-rotatable housing oi the second gripping head, thrust bearing means located between said housing of said second gripping head and the rotatable gripping head thereof so that longitudinally exerted `force can be transmitted to the rotatable head, and means connecting said second gripping head housing and pistons with said frame for preventing relative rotation of thev housing and frame.

5. In a machine for straightening bars of the 'of the'- character described, a frame, two gripping heads mounted on said frame, said heads having housings and having aligned passageways therethrough for the passage oi bars from end to end of and through the machine, bar gripping means in each oi said heads for holding bars at spaced points, anchoring means on the first of said gripping heads adjustably positioning said head on the frame relative to the second head, said second housing being non-rotatable, means connected with the second head for rotating the same, hydraulic cylinders and pistons mounted on said frame on either side of the passageway for the bars through the second head, a crosshead connecting said pistons, longitudinally extending means for connecting said crosshead to said non-rotatable housing of the second gripping head, thrust bearing means located between said housing of said second gripping head and the rotatable gripping head thereof so that longitudinally exerted force can be transmitted to the rotatable head, hydraulic motor return means mounted on said machine and connected with said second housing for moving said housing in a direction opposite to that of the first mentioned hydraulic motor, and means connecting said second gripping head housing and pistons with said iframev for preventing relative rotation of the housing and frame.

6. In a machine for straightening bars of the character described, a frame, two gripping heads mounted on said frame, said heads having housings and having aligned passageways therethrough for the passage o! bars from end to end of and through the machine, bar gripping means in each of said heads for holding bars at spaced points, anchoring means on the first of said gripping heads adjustably positioning said head on the frame relative tothe second head, said second housing being non-rotatable, means connected with the second head for rotating the same, hydraulic cylinders and pistons mounted on said frame on either side of the passageway for the bars through the second head, a crosshead connecting said pistons of said motor, 1ongitudinally extending means for connecting said crosshead to said non-rotatable housing of the second gripping head, thrust bearing means lo cated between said housing of said second gripping head and the rotatable gripping head thereof so that longitudinallyl exerted forcecan be transmitted to the rotatable head, a telescoping bar guide located between said vcrosshead and the rotatable gripping head, hydraulic motor return means mounted on-said machine and connected with said second housing for moving said housing in a direction opposite to that of the first mentioned hydraulic motor, and means connecting said second gripping head housing and pistons with said frame for preventing relative rotation of the housing and frame.

, FRANCIS J. KENT.

REFERENCES CITED The following references are of record in the file of this patent:

v.UNITED STATES PATENTS OTHER REFERENCES Pages 116, irland 11s of Amer. Mach., Maren 

